Image capturing device

Abstract

An image capturing device includes a pixel array having a plurality of pixels arranged in a matrix form, wherein each of the pixels includes a pair of photoelectric conversion devices, an analog to digital converter that converts a pair of pixel signals corresponding to charges accumulated in the pair of photoelectric conversion devices included in each of the pixels into a pair of digital signals, and a circuit receiving the pair of digital signals being output from each of the pixels, detecting a pixel including a photoelectric conversion device outputting a saturation current based on the received pairs in the detected pixel to output a correction signal.

What is claimed is: 
     
       1. An image capturing device comprising:
 a pixel array comprising a plurality of pixels arranged in a matrix form, wherein each of the pixels comprises a pair of photoelectric conversion devices; 
 an analog to digital converter that converts a pair of pixel signals corresponding to charges accumulated in the pair of photoelectric conversion devices included in each of the pixels into a pair of digital signals; and 
 a circuit receiving the pair of digital signals being output from each of the pixels, detecting a pixel of a first group of the pixels including a first photoelectric conversion device outputting a saturation current based on the received pairs, calculating a ratio of digital signals of adjacent pixels in the first group, determining, based on the ratio, whether to correct a digital signal corresponding to the first photoelectric conversion device based on a second group adjacent to the first group, and correcting the digital signal corresponding to the first photoelectric conversion device based on a result of the determining. 
 
     
     
       2. The image capturing device of  claim 1 , wherein the circuit comprises:
 a first circuit that detects the pixel including the first photoelectric conversion device outputting the saturation current to output a first select signal; 
 a second circuit that outputs a second select signal according to the ratio of the digital signals of the adjacent pixels in the first group to which the detected pixel belongs; 
 a third circuit that corrects the digital signal corresponding to the saturation current using a digital signal of an output current of a photoelectric conversion device making a pair with the first photoelectric conversion device outputting the saturation current to output a first correction signal; and 
 a fourth circuit that corrects the digital signal corresponding to the saturation current using a digital signal of a photoelectric conversion device of a position in the second group corresponding to the position of a photoelectric conversion device outputting the saturation current in the first group, to output a second correction signal. 
 
     
     
       3. The image capturing device of  claim 2 , wherein the second group is comprised of pixels that do not output the saturation current. 
     
     
       4. The image capturing device of  claim 2 , further comprising a first multiplexer that outputs a compensation signal based on the first correction signal and the second correction signal according to the second select signal. 
     
     
       5. The image capturing device of  claim 4 , further comprising a summing circuit that outputs a sum signal which is a sum of the pair of digital signals being outputted from the plurality of pixels. 
     
     
       6. The image capturing device of  claim 5 , further comprising a second multiplexer that outputs a correction signal based on the compensation signal and the sum signal according to the first select signal and the second select signal. 
     
     
       7. The image capturing device of  claim 6 , further comprising a signal generator outputting a maximum signal to the second multiplexer. 
     
     
       8. The image capturing device of  claim 1 , wherein the first group comprises two green pixels, one red pixel and one blue pixel. 
     
     
       9. The image capturing device of  claim 2 , wherein the second circuit determines a disparity through block matching using a difference between the pair of digital signals. 
     
     
       10. The image capturing device of  claim 9 , wherein the second select signal and the first correction signal are signals in which the disparity determined by the second circuit is reflected. 
     
     
       11. The image capturing device of  claim 1 , further comprising a filter receiving the pair of digital signals to cancel a noise that occurs in an analog to digital conversion performed by the analog to digital converter. 
     
     
       12. The image capturing device of  claim 1 , wherein the analog to digital converter further comprises a buffer storing the pair of digital signals converted in the analog to digital converter. 
     
     
       13. The image capturing device of  claim 12 , wherein the analog to digital converter sequentially outputs the pair of digital signals stored in the buffer according to an output signal of a timing generator. 
     
     
       14. An image capturing method of an image capturing device comprising a plurality of pixels including at least a first group, the method comprising:
 detecting a pixel in the first group through which a saturation current flows from a pair of digital signals output from a pair of photoelectric conversion devices disposed in each of a plurality of the pixels; 
 determining a first ratio of a digital signal output by a first photoelectric conversion device of a first pixel adjacent the detected pixel in the first group to a digital signal output by a first photoelectric conversion device of a second pixel in the first group adjacent the detected pixel; 
 determining a second ratio of a digital signal output by a second photoelectric conversion device of the first pixel to a digital signal output by a second photoelectric conversion device of the second pixel; 
 performing a first correction using a digital signal of a photoelectric conversion device disposed within the detected pixel that is part of the pair comprising a photoelectric conversion device outputting the saturation current when a similarity between the first ratio and the second ratio is greater than a certain value; and 
 compensating a digital signal of the saturation current of the detected pixel using the first correction. 
 
     
     
       15. The image capturing method of  claim 14 , further comprising performing a second correction using a digital signal of a photoelectric conversion device of a pixel in a second group of the pixels adjacent to the first group when the similarity is smaller than the value.